#include <iostream>
#include <vector>
#include <cstdio>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <functional>
#include "task.h"

typedef std::function<void()> task_t;

void LoadTask(std::vector<task_t> &tasks)
{
    tasks.push_back(PrintLog);
    tasks.push_back(Download);
    tasks.push_back(Backup);
}

int main()
{
    std::vector<task_t> tasks;
    LoadTask(tasks);

    pid_t id = fork();

    if (id == 0)
    {
        // child
        while (true)
        {
            printf("我是子进程, pid : %d\n", getpid());
            sleep(1);
        }
        exit(0);
    }

    // father
    while (true)
    {
        sleep(1);

        pid_t rid = waitpid(id, nullptr, WNOHANG);
        if (rid > 0)
        {
            printf("等待子进程%d 成功\n", rid);
            break;
        }
        else if (rid < 0) 
        {
            printf("等待子进程失败\n");
            break;
        }
        else
        {
            printf("子进程尚未退出\n");

            // 做自己的事情
            for (auto& task : tasks)
            {
                task();
            }
        }
    }

    return 0;
}


